A vehicle, such as, for example, a car, may be propelled electrically. This requires the vehicle to have an electrical energy source, which is typically in the form of a battery. The battery may be fitted in a protective casing that provides fire protection. There may be a risk that the battery catches fire if, for example, the battery is overcharged or malfunctions otherwise. The protective casing may prevent this fire from reaching combustible material in the vehicle, or even explosive material such as, for example, fuel.
A protective battery casing should preferably be lightweight for reasons of, for example, power efficiency. Light weight may also contribute to performance, in terms of speed and acceleration. Carbon fiber-based composites are relatively lightweight and relatively heat resistant, and also relatively strong and stiff. A protective battery casing may thus comprise carbon fiber-based composites. For example, a protective battery casing may comprise walls that have a layered structure including carbon fibers in epoxy resin.